//Given an integer array nums sorted in non-decreasing order, remove the 
//duplicates in-place such that each unique element appears only once. The relative 
//order of the elements should be kept the same. 
//
// Since it is impossible to change the length of the array in some languages, 
//you must instead have the result be placed in the first part of the array nums. 
//More formally, if there are k elements after removing the duplicates, then the 
//first k elements of nums should hold the final result. It does not matter what 
//you leave beyond the first k elements. 
//
// Return k after placing the final result in the first k slots of nums. 
//
// Do not allocate extra space for another array. You must do this by modifying 
//the input array in-place with O(1) extra memory. 
//
// Custom Judge: 
//
// The judge will test your solution with the following code: 
//
// 
//int[] nums = [...]; // Input array
//int[] expectedNums = [...]; // The expected answer with correct length
//
//int k = removeDuplicates(nums); // Calls your implementation
//
//assert k == expectedNums.length;
//for (int i = 0; i < k; i++) {
//    assert nums[i] == expectedNums[i];
//}
// 
//
// If all assertions pass, then your solution will be accepted. 
//
// 
// Example 1: 
//
// 
//Input: nums = [1,1,2]
//Output: 2, nums = [1,2,_]
//Explanation: Your function should return k = 2, with the first two elements 
//of nums being 1 and 2 respectively.
//It does not matter what you leave beyond the returned k (hence they are 
//underscores).
// 
//
// Example 2: 
//
// 
//Input: nums = [0,0,1,1,1,2,2,3,3,4]
//Output: 5, nums = [0,1,2,3,4,_,_,_,_,_]
//Explanation: Your function should return k = 5, with the first five elements 
//of nums being 0, 1, 2, 3, and 4 respectively.
//It does not matter what you leave beyond the returned k (hence they are 
//underscores).
// 
//
// 
// Constraints: 
//
// 
// 0 <= nums.length <= 3 * 10⁴ 
// -100 <= nums[i] <= 100 
// nums is sorted in non-decreasing order. 
// 
// Related Topics Array Two Pointers 👍 5371 👎 8834


package leetcode.editor.en;

public class _26_RemoveDuplicatesFromSortedArray {
    public static void main(String[] args) {
        Solution solution = new _26_RemoveDuplicatesFromSortedArray().new Solution();
    }

    //leetcode submit region begin(Prohibit modification and deletion)
    class Solution {
        public int removeDuplicates2(int[] nums) {
            int l = 0;
            for (int i = 1; i < nums.length; i++) {
                if (nums[l]!=nums[i]){
                    l++;
                    nums[l] = nums[i];
                }
            }
            return l+1;
        }

        public int removeDuplicates1(int[] nums) {
        int slow = 0;
            for (int i = 1; i < nums.length; i++) {
                if (nums[i]!=nums[slow]){
                    slow++;
                    nums[slow] = nums[i];
                }
            }
            return slow+1;
        }




        public int removeDuplicates(int[] nums) {
            int slow = 0;
            int fast = 1;
            while (fast<nums.length){
                if (nums[fast]!=nums[slow]){
                    slow++;
                    nums[slow] = nums[fast];
                }
                fast++;
            }
            return slow+1;
        }
    }
//leetcode submit region end(Prohibit modification and deletion)

}